The present invention relates to a cardiopulmonary resuscitation monitoring apparatus which, in order to enable a rescuer or the like to perform an optimum cardiac massage maneuver when, for example, cardiopulmonary resuscitation is executed, monitors effects of the maneuver.
In order to determine the adequateness of cardiopulmonary resuscitation (CPR) by measuring lung inflation due to the cardiopulmonary resuscitation, a technique using the thoracic impedance is employed. In the lung inflation measurement using the thoracic impedance, however, it is impossible to determine whether blood oxygenation and the blood flow status are improved or not.
On the other hand, a technique using SpO2 in order to monitor blood oxygenation during execution of cardiopulmonary resuscitation is known (see JP-A-2005-46606). During execution of cardiopulmonary resuscitation, however, pulse waves which are effective in a measurement of SpO2 cannot be obtained, and therefore the measurement is sometimes disabled. Moreover, a body motion due to cardiopulmonary resuscitation produces disturbances, and it is difficult to correctly perform the measurement.
It is known that the DC component of transmitted light has information of blood oxygenation, and this is effective in correction of noise contamination (see Japanese Patent No. 3,116,252). However, Japanese Patent No. 3,116,252 discloses only correction corresponding to noise contamination which temporarily occurs in a measurement of SpO2. In the reference, a situation where SpO2 cannot be obtained because pulse waves do not exist in a state where cardiopulmonary resuscitation must be performed is not considered.